Phase I/II trial of topotecan given as continuous infusion in combination with oxaliplatin in 5-FU-pretreated patients with colorectal cancer.

BACKGROUND: Oxaliplatin and topotecan are novel options for a variety of neoplasms. Topotecan has shown fewer side effects and higher efficacy when given as a continuous i.v. infusion compared to single doses, but this regimen has not yet been combined with oxaliplatin. PATIENTS AND METHODS: This phase I/II trial was designed to establish the dose-limiting toxicity of a combination of oxaliplatin (85-130 mg/m2 on day 1) and a continuous infusion of topotecan (initial 0.9 mg/m2 over 72-120 h). Eligible patients with metastatic colorectal cancer had progressive disease during, or within 12 weeks after, palliative fluoropyrimidine-based chemotherapy or in whom intolerable 5-FU toxicity had developed.
RESULTS: The study included 21 patients. Subjectively the treatment was well tolerated but haematological toxicity was observed with the initial treatment schedule of oxaliplatin 85 mg/m2 on day 1 and topotecan 0.9 mg/m2 on days 1-5. Reducing topotecan to 0.9 mg/m2 on days 1-3 resulted also in acceptable haematological toxicity. In patients completing three or more therapy cycles, median progression-free survival was 5 months, and 50% had stable disease or showed a partial response.
CONCLUSION: The recommended dose of this combination for further testing is oxaliplatin 85 mg/m2 on day 1 and topotecan 0.9 mg/m2 per day as a continuous infusion on days 1-3.